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Experimental Study on the Engineering Properties of GelfillAbdul-Hussain, Najlaa January 2011 (has links)
Gelfill (GF) is made of tailings, water, binder and chemical additives (Fillset, sodium silicate gel). The components of GF are combined and mixed on the surface and transported (by gravity and/or pumping) to the underground mine workings, where the GF can be used for both underground mine support and tailings storage.
Thermal (T), hydraulic (H), and mechanical (M) properties are important performance criteria of GF. The understanding of these engineering properties and their evolution with time are still limited due to the fact that GF is a new cemented backfill material.
In this thesis, the evolution of the thermal, hydraulic, mechanical, and microstructural properties of small GF samples are determined. Various binder contents of Portland cement type I (PCI) are used. The GF is cured for 3, 7, 28, 90, and 120 days. It is found that the thermal, hydraulic and mechanical properties are time-dependent or affected by the degree of binder hydration index. Furthermore, a relationship is found between the compressive strength and the saturated hydraulic conductivity of the GF samples.
The unsaturated hydraulic properties of GF samples have also been investigated. The outcomes show that unsaturated hydraulic conductivity is influenced by the degree of binder hydration index and binder content, especially at low suction ranges. Simple functions are proposed to predict the evolution of air-entry values (AEVs), residual water content, and fitting parameters from the van Genuchten model with the degree of hydration index (α). Furthermore, two columns are built to simulate the coupled thermo-hydro-mechanical (THM) behaviour of GF under drained and undrained conditions. The obtained results from the GF columns are compared with the small samples. It is observed that the mechanical properties, hydraulic properties (suction and water content), and temperature development are strongly coupled. The magnitude of these THM coupling factors is affected by the size of the GF. The findings also show that the mechanical, hydraulic and thermal properties of the GF columns are different from samples cured in plastic moulds.
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Studie konstrukce trativodu / Study of Pipe Drain ConstructionNavrátil, Petr January 2014 (has links)
Mixing of backfill of the pipe drain construction with sub-ballast layer material through using enclosed drainage systems (mostly by pipe drains) has to be prevented. In order to do so, regulation SŽDC S4 Železniční spodek provides a filtration criterion which needs to be fulfilled or a geotextile with filtration function has to be used. This master thesis verifies if filtration criteria are fulfilled in between different backfilling of the pipe drains and sub-ballast layers in compliance with TNŽ 73 6949. Furthermore a verification of filtration function of different geotextiles including propositions of their suitable placement within construction of the pipe drain system is included.
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Setzungsarme Bauweisen im Hinterfüllbereich von BrückenwiderlagernSzczyrba, Sebastian 28 June 2013 (has links)
Am Übergang von Brückenbauwerken zu den angrenzenden Hinterfüllungen treten teilweise größere Unebenheiten der Fahrbahnoberfläche im Längsprofil auf. Eine Ursache dafür können Setzungen innerhalb der Hinterfüllung sein. Um diesen Anteil unter realen Bedingungen zu untersuchen, wurden an zwei Autobahnbrücken acht unterschiedlichen Hinterfüllungen ausgeführt und die Verformungen unter Verkehrsbelastung mit einem aufwändigen Messprogramm über einen Beobachtungszeitraum von bis zu vier Jahren erfasst. Im Ergebnis konnte für diese beiden Brücken gezeigt werden, dass die Setzungen unter Verkehrsbelastung nur wenige Millimeter betrugen und deutlich kleiner waren als die Höhenungenauigkeiten beim Einbau der Asphaltdeckschicht. Die Fahrbahnebenheit im Längsprofil wurde allein durch den Zustand vor Verkehrsfreigabe geprägt. Einfache Sofortmaßnahmen zur Erhöhung der Einbaugenauigkeit werden in der Arbeit vorgeschlagen. In einem weiteren Teil werden Erddruck- und Verformungsmessungen an zwei Hinterfüllungen einer integralen Rahmenbrücke vorgestellt.
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Passive Earth Pressures on a Pile Cap with a Dense Sand BackfillMarsh, Robert Ashall 15 December 2009 (has links) (PDF)
Pile groups are often used to provide support for structures. Capping a pile group further adds to the system's resistance due to the passive earth pressure from surrounding backfill. While ultimate passive earth pressure under static loading conditions can be readily calculated using several different theories, the effects of cyclic and dynamic loading on the passive earth pressure response are less understood. Data derived from the full-scale testing of a pile cap system with a densely compacted sand backfill under static, cyclic, and dynamic loadings was analyzed with particular focus on soil pressures measured directly using pressure plates. Based on the testing and analyses, it was observed that under slow, cyclic loading, the backfill stiffness was relatively constant. Under faster, dynamic loading, the observed backfill stiffness decreased in a relatively linear fashion. During cyclic and dynamic loading, the pile cap gradually developed a residual offset from its initial position, accompanied by a reduction in backfill force. While the pile cap and backfill appeared to move integrally during static and cyclic loadings, during dynamic loading the backfill exhibited out-of-phase movement relative to the pile cap. Observed losses in backfill contact force were associated with both cyclic softening and dynamic out-of-phase effects. Force losses due to dynamic loading increased with increasing frequency (which corresponded to larger displacements). Losses due to dynamic loading were offset somewhat by increases in peak force due to damping. The increase in contact force due to damping was observed to be relatively proportional to increasing frequency. When quantifying passive earth forces with cyclic/dynamic losses without damping, the Mononobe-Okabe (M-O) equation with a 0.75 or 0.8 multiplier applied to the peak ground acceleration can be used to obtain a reasonable estimate of the force. When including increases in resistance due to damping, a 0.6 multiplier can similarly be used.
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Vojenské muzeum v Králíkách - stavebně technologický projekt / Military museum Kraliky - planning of implementation and management of constructionKucsera, Adam January 2014 (has links)
This thesis is aimed at the Military Museum in Kraliky. This construction made on the basis of the initial design of the designer. For this reason, it was necessary to deal with during the processing work some technical problems, transport of materials to the construction site or purely site layout itself. The whole area of the museum consists of several buildings. The largest and main building of the exposition hall with steel supporting structures, then there is the Administration building, which in turn is a brick workshop that has as Exp hall steel structure. There is also a replica of the First Republic Military cottage, which has a wooden frame and demonstration area, where there will be live demonstrations of military equipment.
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Stavebně technologický projekt výstavby sportovní haly / Construction technological project of sports hall constructionTkáč, Jiří January 2022 (has links)
The thesis deals with Komenského Street sports hall construction in Lysá nad Labem. Although partially dealing with construction of all parts, in detail it studies gym construction, focusing on time management, technology and resources of implementation. The thesis is divided into the drawing and text parts. The former includes site facilities design and building situation. The latter consists of the main part construction project implementation study, itemized budget, time schedule, technological regulations, inspection and testing plan for the implementation of the main construction part 1st floor reinforced concrete columns and walls, construction machines and mechanisms design as well as time and financial schedule.
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